* Resolution authorizes inspection of North Korea cargo
* China says move shows world's firm opposition
(Adds U.S., British and Japanese envoys, details)
By Louis Charbonneau and Claudia Parsons
UNITED NATIONS, June 12 (Reuters) - The Security Council on Friday unanimously approved wider U.N. sanctions against North Korea over its May 25 nuclear test, a move which close ally China said showed firm opposition to Pyongyang's atomic ambitions.
The sanctions resolution banned all weapons exports from North Korea and most arms imports into the reclusive Communist state. It authorized U.N. member states to inspect North Korean sea, air and land cargo, requiring them to seize and destroy any goods transported in violation of the sanctions.
Both China and Russia, which had been reluctant to support punitive measures against North Korea in the past, endorsed the U.S.-drafted resolution, which is now binding under international law.
China's U.N. ambassador, Zhang Yesui, said the resolution showed the "firm opposition" of the international community to North Korea's nuclear ambitions, but he urged countries to exercise caution when inspecting North Korean cargo.
"Under no circumstances should there be use or threat of the use of force," Zhang said, adding that the inspections should be done in line with domestic and international law.
U.S. Ambassador to the United Nations Susan Rice said Washington would press to ensure that the resolution was fully implemented and would not get into a "tit-for-tat reaction" to every provocation from Pyongyang.
"It would not be a surprise if North Korea reacted to this very tough sanctions regime in a fashion that would be further provocation and further destabilizing," she said in Washington.
BELLIGERENT THREATS
North Korea, which prompted a period of high tension in the region with the nuclear explosion followed by a series of missile tests and belligerent threats, did not send a representative to speak at the Security Council meeting.
Japanese Ambassador Yukio Takasu welcomed the resolution but acknowledged that it did not permit the use of force, even during the inspection of suspicious North Korea cargo.
"The inspections regime on the open seas should be on the basis of cooperation and consent," he said, adding that if a North Korean ship refused inspection, the only recourse was to report it to the Security Council.
During more than two weeks of negotiations on the draft resolution, the United States and Japan had pushed to authorize forced inspections of suspicious air, land and sea cargo. But diplomats said Russia and China had made clear they would veto the resolution unless the inspections were based on consent.
The resolution did speak of a "required inspection" if a ship refuses to be inspected. However, the ship's flag country could then send the vessel to any port it chooses where the local authorities would carry out any cargo inspection.
This, analysts says, weakened the inspection regime.
All financial transactions with North Korea that could contribute to its nuclear or ballistic missile programs will remain banned. The resolution urges, but does not require, states and institutions not to make new grants or loans to North Korea, except for humanitarian or development aid.
Council diplomats said on condition of anonymity that it was not clear whether China, which is the closest its neighbor North Korea has to a major ally, was prepared to actively implement the new sanctions resolution.
CHINA'S COMMITMENT
Beijing had ignored an earlier round of sanctions against Pyongyang passed after North Korea's first nuclear test in October 2006. But the diplomats said that China had become increasingly frustrated with North Korea and it was more likely to help implement the sanctions now than ever before.
Even Libya and Vietnam, two non-permanent members of the 15-member council which had expressed reservations about punishing North Korea, backed the resolution, which is officially designated Resolution 1874.
Rice, who sent a deputy to cast the "yes" vote for the United States, told a White House briefing that the resolution was "unprecedented" and created a sanctions regime that has "teeth that will bite."
Russian Ambassador Vitaly Churkin said the sanctions resolution was an "appropriate" and "balanced" response to Pyongyang's nuclear test, which he said "jeopardizes security and stability in the region."
The new resolution broadened the arms embargo against North Korea to ban the sale of all arms -- heavy and small -- by Pyongyang, but allowed it to keep purchasing small arms. Diplomats said it was the Chinese who argued against banning the sale of small arms to Pyongyang.
The resolution urged North Korea to return to the six-nation aid-for-disarmament talks with the United States, China, Russia, Japan and South Korea and offered the possibility of suspending sanctions if North Korea changed course.
Britain's Deputy Ambassador Philip Parham said the sanctions targeted Pyongyang's nuclear and missile programs and would not hit the North's already impoverished population. (Additional reporting by David Alexander in Washington; Editing by David Storey)